[Bf-blender-cvs] [06fd4c3617c] viewport-compositor: Viewport Compositor: Port Difference Key node

[Omar Emara]

Commit: 06fd4c3617c5398807230d68533928fc06d3328a
Author: Omar Emara
Date:   Wed Nov 17 21:11:45 2021 +0200
Branches: viewport-compositor
https://developer.blender.org/rB06fd4c3617c5398807230d68533928fc06d3328a

Viewport Compositor: Port Difference Key node

This patch ports the Difference Key node to the viewport compositor. The
shader is a straightforward port of the compositor code.

===================================================================

M	source/blender/gpu/CMakeLists.txt
M	source/blender/gpu/intern/gpu_material_library.c
A	source/blender/gpu/shaders/composite/gpu_shader_composite_difference_matte.glsl
M	source/blender/nodes/composite/nodes/node_composite_diffMatte.cc

===================================================================

diff --git a/source/blender/gpu/CMakeLists.txt b/source/blender/gpu/CMakeLists.txt
index 5d99f14dc6b..3dfedf13d8e 100644
--- a/source/blender/gpu/CMakeLists.txt
+++ b/source/blender/gpu/CMakeLists.txt
@@ -294,6 +294,7 @@ data_to_c_simple(shaders/composite/gpu_shader_composite_color_matte.glsl SRC)
 data_to_c_simple(shaders/composite/gpu_shader_composite_color_spill.glsl SRC)
 data_to_c_simple(shaders/composite/gpu_shader_composite_color_to_luminance.glsl SRC)
 data_to_c_simple(shaders/composite/gpu_shader_composite_composite.glsl SRC)
+data_to_c_simple(shaders/composite/gpu_shader_composite_difference_matte.glsl SRC)
 data_to_c_simple(shaders/composite/gpu_shader_composite_ellipse_mask.glsl SRC)
 data_to_c_simple(shaders/composite/gpu_shader_composite_exposure.glsl SRC)
 data_to_c_simple(shaders/composite/gpu_shader_composite_gamma.glsl SRC)
diff --git a/source/blender/gpu/intern/gpu_material_library.c b/source/blender/gpu/intern/gpu_material_library.c
index f44abf4ee60..b553b62b77f 100644
--- a/source/blender/gpu/intern/gpu_material_library.c
+++ b/source/blender/gpu/intern/gpu_material_library.c
@@ -60,6 +60,7 @@ extern char datatoc_gpu_shader_composite_color_matte_glsl[];
 extern char datatoc_gpu_shader_composite_color_spill_glsl[];
 extern char datatoc_gpu_shader_composite_color_to_luminance_glsl[];
 extern char datatoc_gpu_shader_composite_composite_glsl[];
+extern char datatoc_gpu_shader_composite_difference_matte_glsl[];
 extern char datatoc_gpu_shader_composite_ellipse_mask_glsl[];
 extern char datatoc_gpu_shader_composite_exposure_glsl[];
 extern char datatoc_gpu_shader_composite_gamma_glsl[];
@@ -255,6 +256,11 @@ static GPUMaterialLibrary gpu_shader_composite_composite_library = {
     .dependencies = {NULL},
 };
 
+static GPUMaterialLibrary gpu_shader_composite_difference_matte_library = {
+    .code = datatoc_gpu_shader_composite_difference_matte_glsl,
+    .dependencies = {NULL},
+};
+
 static GPUMaterialLibrary gpu_shader_composite_ellipse_mask_library = {
     .code = datatoc_gpu_shader_composite_ellipse_mask_glsl,
     .dependencies = {NULL},
@@ -831,6 +837,7 @@ static GPUMaterialLibrary *gpu_material_libraries[] = {
     &gpu_shader_composite_color_spill_library,
     &gpu_shader_composite_color_to_luminance_library,
     &gpu_shader_composite_composite_library,
+    &gpu_shader_composite_difference_matte_library,
     &gpu_shader_composite_ellipse_mask_library,
     &gpu_shader_composite_exposure_library,
     &gpu_shader_composite_gamma_library,
diff --git a/source/blender/gpu/shaders/composite/gpu_shader_composite_difference_matte.glsl b/source/blender/gpu/shaders/composite/gpu_shader_composite_difference_matte.glsl
new file mode 100644
index 00000000000..d769cadce3c
--- /dev/null
+++ b/source/blender/gpu/shaders/composite/gpu_shader_composite_difference_matte.glsl
@@ -0,0 +1,10 @@
+void node_composite_difference_matte(
+    vec4 color, vec4 key, float tolerance, float falloff, out vec4 result, out float matte)
+{
+  vec4 difference = abs(color - key);
+  float average_difference = (difference.r + difference.g + difference.b) / 3.0;
+  bool is_opaque = average_difference > tolerance + falloff;
+  float alpha = is_opaque ? color.a : (max(0.0, average_difference - tolerance) / falloff);
+  matte = min(alpha, color.a);
+  result = color * matte;
+}
diff --git a/source/blender/nodes/composite/nodes/node_composite_diffMatte.cc b/source/blender/nodes/composite/nodes/node_composite_diffMatte.cc
index 1e1a48381b7..6eb66be466d 100644
--- a/source/blender/nodes/composite/nodes/node_composite_diffMatte.cc
+++ b/source/blender/nodes/composite/nodes/node_composite_diffMatte.cc
@@ -44,6 +44,23 @@ static void node_composit_init_diff_matte(bNodeTree *UNUSED(ntree), bNode *node)
   c->t2 = 0.1f;
 }
 
+static int node_composite_gpu_diff_matte(GPUMaterial *mat,
+                                         bNode *node,
+                                         bNodeExecData *UNUSED(execdata),
+                                         GPUNodeStack *in,
+                                         GPUNodeStack *out)
+{
+  const NodeChroma *data = (NodeChroma *)node->storage;
+
+  return GPU_stack_link(mat,
+                        node,
+                        "node_composite_difference_matte",
+                        in,
+                        out,
+                        GPU_uniform(&data->t1),
+                        GPU_uniform(&data->t2));
+}
+
 void register_node_type_cmp_diff_matte(void)
 {
   static bNodeType ntype;
@@ -53,6 +70,7 @@ void register_node_type_cmp_diff_matte(void)
   node_type_socket_templates(&ntype, cmp_node_diff_matte_in, cmp_node_diff_matte_out);
   node_type_init(&ntype, node_composit_init_diff_matte);
   node_type_storage(&ntype, "NodeChroma", node_free_standard_storage, node_copy_standard_storage);
+  node_type_gpu(&ntype, node_composite_gpu_diff_matte);
 
   nodeRegisterType(&ntype);
 }